Now Olga gave to each soldier in her army a pigeon or a
sparrow, and ordered them to attach by thread to each
pigeon and sparrow a piece of sulfur bound with small
pieces of cloth. When night fell, Olga bade her soldiers
release the pigeons and the sparrows. So the birds flew
to their nests, the pigeons to the cotes, and the
sparrows under the eaves. The dove-cotes, the coops, the
porches, and the haymows were set on fire. There was not
a house that was not consumed, and it was impossible to
extinguish the flames, because all the houses caught on
fire at once.
...but no explanation for the spontaneous combustion of the cloth-bound sulfur.Sounds like it was probably a closely-kept, obfuscated military secret like Greek Fire:
This is why keeping oily rags are a fire hazard.
I found this out as a child by accident and set fire to the desk in my bedroom...
To be fair that desk caught fire quite a few times.
He once really stalled on us, we were stuffing an empty 7.62 cartridge with explosives and he very clearly explained that while he though we shouldn't make fireworks at least we shouldn't use metal parts.
We continued with a small plastic tube and a couple of hours later it went off in my hand. I love my Dad for a lot of reasons.
We weren't blessed with such weaponry in the UK. About all we got was 12 gauge shotgun cartridges and anything we made ourselves. The latter included ANFO so we made up for it through chemistry. This was 25 years ago; doing this now would get you chucked in prison in 2 seconds flat.
Regarding Olga, she christianized Rus and here sainthood was recognition of that. I don't actually know if she was ever considered a saint by the Roman Church.